There have a been a few who have tried them. Denzo did as well as one other member I remember. Denzo found his misfire to be tuned based, since as soon as he switched away from one tune to another things were fine.

I think the Okada coils are still up in the air, in terms of how useful they are. Some of the PTF people are using them, as are a few big whp N54 guys, I think Enrita uses them as well. Angerman if you've already swapped out coils and plugs, valve cleaning would be a good place to go next. Not cheap I know Or perhaps you have a leaky injector, not too common but it happens. Ugh just thinking about misfires makes my head spin.